It is a signal honour to have been asked to deliver this lecture to commemorate the outstanding contributions of Jean Baer and Julian Huxley to the cause of conservation. Both of these great men devoted their genius as scientists to helping us to broaden our perceptions of the human condition and their talents as leaders to establishing the institutions needed to safeguard and to improve the conditions of life on this planet. No two individuals did more to establish the foundations on which environmental conservation can now be seen and dealt with as a critical global issue.

Large natural preserves, known as zapovedniki, represent the main territorial entities employed in biosphere preservation in the Soviet Union. In the past decade, a large expansion of the zapovedniki system has taken place, 35 new preserves totalling 4,477,000 ha having been created. In all, the system totalled (in 1976) 107 preserves covering about nine million hectares. The period since 1970 has also seen the creation of the U.S.S.R.'s first three national parks, one in each of the three Baltic republics.

Both zapovedniki and national parks in the Soviet Union are still in the process of having uniform administrative policies formulated for their management, which represents a difficult task in view of the fact that they have traditionally been managed by a wide variety of concerned agencies.

The zapovedniki network represents one of the great biosphere preservation systems of the world, and remaining problems associated with ecosystem management, tourism, economic uses, and administrative coordination, are being given thoughtful attention.

After stressing the importance of the plant kingdom to Man and the dangers threatening the survival of an estimated 20,000 species of flowering plants, this paper presents details of the activities of the IUCN Threatened Plants Committee (TPC), set up by the Survival Service Commission in 1974. The Secretariat of the TPC works through three main approaches: (1) regional groups of botanists and other experts identifying threats to their floras, advising the TPC, and preparing recommendations; (2) specialist groups doing similar work for plant groups such as palms and cycads; and (3) institutional support of botanic gardens and similar organizations maintaining collections of threatened species in cultivation. This last aspect was launched at a conference on conservation held at Kew in 1975.

The primary aim of the TPC is to gather and disseminate information on which species are threatened throughout the world. Accurate documentation is essential, and in this task both herbarium and field work are needed. Although our knowledge in general of temperate, subtropical, and islands, floras is reasonably good in most cases, and there are specialists working on most of such areas, our knowledge of continental tropical floras is much less comprehensive. There is an urgent need for check-lists to be rapidly compiled for such areas wherever possible. In tropical rain-forests, the difficulties encountered in listing threatened species are particularly acute.

Provided present collaboration continues and finance is provided, initial lists of rare and threatened species will become available within the next decade for many areas. This information should be of great value in preventing needless extinction through lack of planning or forethought, in providing a valuable input in the selection of sites for reserves, etc., and in complementing habitat conservation approaches—as well as helping to stimulate action on individual species.

The ‘Red Data’ categories used by IUCN to indicate the degrees of threat to individual species are outlined, and will be used in the three types of TPC publication—regional lists of rare and threatened species, bulletins on smaller areas with more detail on each species, and sheets for the Red Data Book which will give detailed case-histories of a limited selection of threatened species. All three approaches are under way; the European List has been completed, bulletins for many areas are on the way, and the TPC aims to start issuing new plant Red Data sheets in 1977–78.

The environmental problems which may arise in India, due to population growth, increased industrial and agricultural activities, and depletion of natural resources in the next 25 years, are discussed here. Selected aspects of problems which require special attention are treated with particular emphasis on rural situations. The present status of the various aspects of human settlement—such as quality of air, water, sanitation, health, and housing—as well as aspects of conservation of forests, soils, and wildlife, is outlined as far as possible in a quantitative manner. It is visualized that environmental management will have to be more serious and of growing dimensions in the coming years.

It emerges from the study that two of the most serious problems which India may face in 25 years' time are water pollution and deforestation. By a.d. 2000, population in India is projected to reach around 950 millions, 65% of whom would be living in rural areas. The environment's capacity to absorb the concomitant wastes and pollution would be significantly reduced through the consequent growth of human activities. At present, in the rural areas, the percentage of population with piped water-supply and exclusive sanitation facilities is less than 10%. Unless drastic measures are taken, this percentage may not exceed 30% by A.D. 2000. Without appropriate sewerage and sanitation facilities, the accumulated wastes could mix with open-water resources, so leading to high levels of water pollution. The effects of mixing agricultural runoff containing wastes, pesticides, and fertilizers, in the rural water-sources, would also need consideration.

The current practice in the rural areas of obtaining more than 90% of domestic fuels from non-commercial sources—firewood, animal dung, and agricultural wastes—even if considerably reduced, may continue and lead to deforestation and hence to soil erosion, floods, climatic changes, and loss of precious varieties of flora and fauna. Such burning leads to air pollution as well.

Apart from the problems of water pollution and deforestation, the problems of the urban areas include increasing slums, inadequate transportation facilities, and industrial pollution—all of which would have to be dealt with. Finally, the present status of environmental legislation is reviewed, and certain policies and intense efforts for generating environmental awareness are recommended.

Ecological interrelationships are far less complex in the desert biome than they are in grassland or forest but, even so, they are little understood. Some of the better known are described, but none of them is relevant to desertification. Harmful insects, such as locusts, grasshoppers, and termites, are unlikely to be responsible for extension of desert, except when they intensify environmental changes that have already been initiated by Man. Similarly, mammalian herbivores, even if protected and allowed to attain far greater population sizes than at present, are most unlikely to cause harm, as they are highly nomadic and always on the move.

These relationships hold true despite the fact that the natural predators of desert mammalian herbivores have largely been eliminated by human activities.

Among the larger mammals, marine types offer some unique insights and problems for management. United States laws require that they be managed ‘to maintain the health and stability of the marine ecosystem.’ The relevant statute (Marine Mammal Protection Act of 1972) requires maintenance of an ‘optimal sustainable population’, which is being interpreted as a range between the level giving a maximum sustainable yield (MSY) and asymptotic levels. Emerging evidence pertaining to marine mammals, and perhaps applicable to a larger class of vertebrates, indicates that the MSY point may be well above the logistic-curve 50% point.

‘Reproduction curves’ of various sorts are used in management as operational representations of population self-regulation (density-dependence). A variety of theories and hypotheses concerning such regulation now exists, though none is adequately supported as yet. A general model for self-regulation in long-lived species is suggested as being comprised of stages of regulation. Immature mortality is postulated as the first stage, followed by age of first reproduction and then reproductive rates of adult females. The fourth and last stage, as populations reach maximum sustainable levels, is assumed to involve changes in adult survival.

Although a model of the kind suggested here offers some useful insights as to harversting strategies, a more quantitative (functional) basis will be needed for actual management applications.

Marine and terrestial animals have been shown to be particularly abundant in a wildlife community associated with a marine sewer outfall from the City of Vancouver. These same animals are contaminated with high levels of heavy-metals but are apparently protected from their poisonous effects by the production of a protein known as metallothionein. The amount of metallothionein and heavy-metal loading appears to depend primarily on the degree of pollution and secondly on the species of animal and its position in the food-web.

The need to conserve representative samples of natural vegetation was recognized in Nigeria over thirty years ago. Before 1950 only two conservation areas had been laid down but at present there are seven in operation. Most of them are between 60 ha (ca 1/4 sq. mile) and 350 ha (ca 12/5 sq. miles) in area, and together they include at least one example of each major ecological type occurring in the country.

There are difficulties in constituting and safeguarding conservation areas, particularly outside State Forest Reserves. While it is to be hoped that legislation will soon be introduced to facilitate protection, a comprehensive survey has recently been carried out with a view to substantially increasing the number of conservation areas in Nigeria, and to make them more fully representative of the different vegetation zones of Nigeria.

Work is also proceeding towards determining the optimum size for each area within the different vegetation types. It is hoped to be able to establish up to 40 conservation areas within the next 2 years, and ultimately as many as 110 may be designated.

A total of 2,816 questionnaires were completed in the Dalby Forest Area in the period from March 1975 to March 1976. The answers to six questions were combined into a wildlife interest index. These questions were concerned with: (1) the interviewees' commitments to a wildlife organization, (2) the interviewees’ activities in the Area, (3) the elements of the Area which increased the interviewees' enjoyment, (4) benefits that the interviewees felt from visiting the Area, (5) the wildlife that interviewees has seen or hoped to see, and (6) the interviewees' desire to use a hide.

The interviewees' interest in wildlife was made up of an appreciation of the aesthetic, emotive, and psychological, elements of wildlife, as well as a purely active pursuit in nature study. These attributes of wildlife are all aspects which should be taken into consideration when assessing the role of wildlife in the recreational qualities of an area.